package com.atguigu.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.es.SkuEsModel;
import com.atguigu.common.utils.R;
import com.atguigu.gulimall.search.config.GulimallElasticSearchConfig;
import com.atguigu.gulimall.search.constant.EsConstant;
import com.atguigu.gulimall.search.feign.ProductFeignService;
import com.atguigu.gulimall.search.service.MallSearchService;
import com.atguigu.gulimall.search.vo.AttrResponseVo;
import com.atguigu.gulimall.search.vo.BrandVo;
import com.atguigu.gulimall.search.vo.SearchParam;
import com.atguigu.gulimall.search.vo.SearchResult;
import org.apache.commons.lang.StringUtils;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.Aggregation;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * Data time:2022/4/2 16:43
 * StudentID:2019112118
 * Author:hgw
 * Description:
 */
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient client;

    @Autowired
    ProductFeignService productFeignService;

    @Override
    public SearchResult search(SearchParam param) {
        // 动态的构建出查询的DSL语句
        SearchResult result = null;

        // 1、准备检索请求
        SearchRequest searchRequest = buildSearchRequrest(param);

        try {
            // 2、执行检索请求
            SearchResponse response = client.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);

            // 3、分析相应数据并封装成需要的指定格式
            result = buildSearchResult(response,param);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }


    /**
     * 准备检索请求
     * 模糊匹配：过滤（按照属性、分类、品牌、价格区间、库存）、排序、分页、高亮，聚合分析
     * @return SearchRequest
     */
    private SearchRequest buildSearchRequrest(SearchParam param) {
        // 构建DSL语句的
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();

        /**
         * 查询：模糊匹配，过滤（按照分类、品牌、属性、库存、价格区间）
         */
        // 1、构建bool-query
        BoolQueryBuilder boolBuilder = QueryBuilders.boolQuery();
        // 1.1、match-模糊匹配
        if (!StringUtils.isEmpty(param.getKeyword())) {
            boolBuilder.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }

        // 1.2、filter-过滤（按照分类、品牌、属性、库存、价格区间）
        // 1.2.1、按照三级分类id查询
        if (param.getCatalog3Id() != null) {
            boolBuilder.filter(QueryBuilders.termQuery("catalogId", param.getCatalog3Id()));
        }
        // 1.2.2、按照品牌id查询
        if (param.getBrandId() != null && param.getBrandId().size()>0) {
            boolBuilder.filter(QueryBuilders.termsQuery("brandId", param.getBrandId()));
        }
        // 1.2.3、按照所有指定的属性进行查询
        if (param.getAttrs()!=null && param.getAttrs().size()>0) {
            for (String attrStr : param.getAttrs()) {
                // attrs=1_其他:安卓&attrs=2_5寸:1.5寸
                BoolQueryBuilder nestedBoolBuilder = QueryBuilders.boolQuery();
                String[] s = attrStr.split("_");
                String attrId = s[0];   // 检索的属性id
                String[] attrValues = s[1].split(":");  // 这个属性检索用的值
                nestedBoolBuilder.must(QueryBuilders.termQuery("attrs.attrId",attrId));
                nestedBoolBuilder.must(QueryBuilders.termsQuery("attrs.attrValue",attrValues));
                // 每一个必须都得生成一个嵌入式的查询nested
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", nestedBoolBuilder, ScoreMode.None);
                boolBuilder.filter(nestedQuery);
            }
        }
        // 1.2.4、按照是否拥有库存进行查询
        if (param.getHasStock() != null) {
            boolBuilder.filter(QueryBuilders.termQuery("hasStock", param.getHasStock()==1));
        }
        // 1.2.5、按照价格区间进行查询
        if (!StringUtils.isEmpty(param.getSkuPrice())){
            // 1_500/_500/500_
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            String[] s = param.getSkuPrice().split("_");
            if (s.length==2){
                // 区间
                rangeQuery.gte(s[0]).lte(s[1]);
            } else if (s.length == 1) {
                if (param.getSkuPrice().startsWith("_")) {
                    rangeQuery.lte(s[0]);
                }
                if (param.getSkuPrice().endsWith("_")) {
                    rangeQuery.gte(s[0]);
                }
            }
            boolBuilder.filter(rangeQuery);
        }

        // 把以前的所有条件都拿来进行封装
        sourceBuilder.query(boolBuilder);

        /**
         * 排序、分页、高亮
         */
        // 2、排序
        if (!StringUtils.isEmpty(param.getSort())){
            String sort = param.getSort();
            // sort=saleCount_desc/asc
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc")?SortOrder.ASC:SortOrder.DESC;
            sourceBuilder.sort(s[0], order);
        }
        // 3、分页
        sourceBuilder.from((param.getPageNum()-1)*EsConstant.PRODUCT_PAGESIZE);
        sourceBuilder.size(EsConstant.PRODUCT_PAGESIZE);
        // 4、高亮
        if (!StringUtils.isEmpty(param.getKeyword())) {
            HighlightBuilder highlightBuilder = new HighlightBuilder();
            highlightBuilder.field("skuTitle");
            highlightBuilder.preTags("<b style='color:red'>");
            highlightBuilder.postTags("</b>");
            sourceBuilder.highlighter(highlightBuilder);
        }


        /**
         * 聚合分析
         */
        // 5.1、品牌聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(50);
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1)); // 品牌聚合的子聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        // TODO 1、聚合brand
        sourceBuilder.aggregation(brand_agg);
        // 5.2、分类聚合
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg").field("catalogId").size(20);
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        // TODO 2、聚合catalog
        sourceBuilder.aggregation(catalog_agg);
        // 5.3、属性聚合
        NestedAggregationBuilder attrs_agg = AggregationBuilders.nested("attrs_agg", "attrs"); // 嵌入聚合
        // 聚合出当前所有的attrId
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        // 聚合分析出当前attr_id对应的名字
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        // 聚合分析出当前attr_id对应所有可能的属性值attrValue
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        attrs_agg.subAggregation(attr_id_agg);
        // TODO 3、聚合attr
        sourceBuilder.aggregation(attrs_agg);

        SearchRequest searchRequest = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX}, sourceBuilder);
        return searchRequest;
    }


    /**
     * 构建结果数据
     * @param response  执行检索请求获得的响应数据
     * @return  封装成需要的指定格式并返回
     */
    private SearchResult buildSearchResult(SearchResponse response, SearchParam param) {

        SearchResult result = new SearchResult();

        // 1、返回的所有查询到的商品
        SearchHits hits = response.getHits();
        List<SkuEsModel> esModels = new ArrayList<>();
        if (hits.getHits()!=null && hits.getHits().length>0) {
            for (SearchHit hit : hits.getHits()) {
                String sourceAsString = hit.getSourceAsString();
                SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);
                if (!StringUtils.isEmpty(param.getKeyword())) {
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String string = skuTitle.getFragments()[0].string();
                    esModel.setSkuTitle(string);
                }
                esModels.add(esModel);
            }
        }
        result.setProducts(esModels);



        // 2、当前所有商品涉及到的所有属性信息
        List<SearchResult.AttrVo> attrVos = new ArrayList<>();
        ParsedNested attrs_agg = response.getAggregations().get("attrs_agg");
        ParsedLongTerms attr_id_agg = attrs_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            // 1、得到属性的id
            long attrId = bucket.getKeyAsNumber().longValue();
            // 2、得到属性的名字
            String attrName = ((ParsedStringTerms) bucket.getAggregations().get("attr_name_agg")).getBuckets().get(0).getKeyAsString();
            // 3、得到属性的所有值
            List<String> attrValues = ((ParsedStringTerms) bucket.getAggregations().get("attr_value_agg")).getBuckets().stream().map(item -> {
                String keyAsString = ((Terms.Bucket) item).getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());
            attrVo.setAttrId(attrId);
            attrVo.setAttrName(attrName);
            attrVo.setAttrValue(attrValues);

            attrVos.add(attrVo);
        }
        result.setAttrs(attrVos);

        // 3、保存当前商品所涉及的所有品牌信息
        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");
        for (Terms.Bucket bucket : brand_agg.getBuckets()) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();
            // 1、得到品牌的id
            long brandId = bucket.getKeyAsNumber().longValue();
            // 2、得到品牌的name
            String brandName = ((ParsedStringTerms) bucket.getAggregations().get("brand_name_agg")).getBuckets().get(0).getKeyAsString();
            // 3、得到品牌的img
            String brandImg = ((ParsedStringTerms) bucket.getAggregations().get("brand_img_agg")).getBuckets().get(0).getKeyAsString();
            brandVo.setBrandId(brandId);
            brandVo.setBrandImg(brandName);
            brandVo.setBrandImg(brandImg);
            brandVos.add(brandVo);
        }
        result.setBrands(brandVos);

        // 4、保存当前商品所涉及的所有分类信息
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");
        List<? extends Terms.Bucket> buckets = catalog_agg.getBuckets();
        for (Terms.Bucket bucket : buckets) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            // 得到分类id
            catalogVo.setCatalogId(bucket.getKeyAsNumber().longValue());
            // 得到分类name
            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String catalog_name = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalog_name);
            catalogVos.add(catalogVo);
        }
        result.setCtatLogs(catalogVos);

        // 5、分页信息
        // 分页信息-页码
        result.setPageNum(param.getPageNum());
        // 分页信息-总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);
        // 分页信息-总页码 (总记录数 对 每页数求余数）
        int totalPages = (int)total%EsConstant.PRODUCT_PAGESIZE==0 ? ((int)total/EsConstant.PRODUCT_PAGESIZE) : ((int)total/EsConstant.PRODUCT_PAGESIZE+1);
        result.setTotalPages(totalPages);
        // 分页信息-导航栏
        List<Integer> pageNavs = new ArrayList<>();
        for (int i = 1; i <= totalPages; i++) {
            pageNavs.add(i);
        }
        result.setPageNavs(pageNavs);


        // 6、构建面包屑导航功能
        if (param.getAttrs()!=null && param.getAttrs().size()>0 ) {
            List<SearchResult.NavVO> navVOs = param.getAttrs().stream().map(attr -> {
                // 1、分析每一个attrs传过来的查询参数值
                SearchResult.NavVO navVO = new SearchResult.NavVO();
                String[] s = attr.split("_");
                navVO.setNavValue(s[1]);
                R r = productFeignService.attrInfo(Long.parseLong(s[0]));
                result.getAttrIds().add(Long.parseLong(s[0]));
                if (r.getCode()==0) {
                    AttrResponseVo data = r.getData("attr", new TypeReference<AttrResponseVo>() {
                    });
                    navVO.setNavName(data.getAttrName());
                } else {
                    navVO.setNavName(s[0]);
                }
                // 2、取消了这个面包屑以后，我们要跳转到哪个地方。将请求地址的url里面的当前条件置空
                // 拿到所有的查询条件，去掉当前。
                String replace = replaceQueryString(param, attr,"attrs");
                navVO.setLink("http://search.gulimall.cn/list.html?"+replace);
                return navVO;
            }).collect(Collectors.toList());

            result.setNavs(navVOs);
        }
        // 7、品排、分类
        if (param.getBrandId()!=null && param.getBrandId().size()>0) {
            List<SearchResult.NavVO> navs = result.getNavs();
            SearchResult.NavVO navVO = new SearchResult.NavVO();
            navVO.setNavName("品牌");
            // TODO 远程查询所有品牌
            R r = productFeignService.brandsInfo(param.getBrandId());
            if (r.getCode()==0) {
                List<BrandVo> brand = r.getData("brand", new TypeReference<List<BrandVo>>() {
                });
                StringBuffer buffer = new StringBuffer();
                String replace = "";
                for (BrandVo brandVo : brand) {
                    buffer.append(brandVo.getBrandName()+";");
                    replace = replaceQueryString(param, brandVo.getBrandId()+"" ,"brandId");
                }
                navVO.setNavValue(buffer.toString());
                navVO.setLink("http://search.gulimall.cn/list.html?"+replace);
            }
            navs.add(navVO);
        }
        return result;
    }

    // TODO 分类：不需要导航取消



    private String replaceQueryString(SearchParam param, String value,String key) {
        String encode = null;
        try {
            encode = URLEncoder.encode(value, "UTF-8");
            encode = encode.replace("+", "%20"); // 浏览器对空格的编码和Java不一样
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        String replace = param.get_queryString().replace("&"+key+"=" + encode, "");
        return replace;
    }
}
